loop-mcp MCP Server

by loopxxi Your server? Claim it

answering

loop-mcp is answering right now. Last checked 9 min ago. It exposes 16 tools.

15 pay-per-call Bitcoin and developer tools, paid in sats over Lightning (L402).

The linked repository no longer exists on GitHub — it was deleted or made private.

Uptime history 91 days of history · worst day 0%

91 days agonow

100.0%

Uptime 24h

91 of 91 checks

Tools

read from the server

406 ms

Response time

average over 24h

open, no key

Access

streamable-http

What changed 64

Every tool that appeared, vanished or quietly changed what it asks for. Recorded since 27 October 2026. No other catalogue keeps this.

4 Nov a tool appeared business_ratios

4 Nov a tool changed version

3 Nov 15 tool descriptions were rewritten16 times that day base64_convert, btc_price, btc_send_decision and 12 more

3 Nov 15 tools changed the parameters they ask for base64_convert, btc_price, btc_send_decision and 12 more

3 Nov a tool changed version

27 Oct 15 tool descriptions were rewritten base64_convert, btc_price, btc_send_decision and 12 more

27 Oct 15 tools changed the parameters they ask for base64_convert, btc_price, btc_send_decision and 12 more

and 1 more, back to 27 October 2026

This one has been quiet for a while

Quiet is not dead — but it is worth knowing when it wakes up, or when someone else takes it over. We watch the repository and tell you either way.

Connect this server

Endpoint below is the one we actually reach during checks — not the one copied from a README. Last verified 9 min ago.

Claude Code Claude Desktop Codex Cursor VS Code

run in your terminal

claude mcp add loop-mcp --transport http https://mcp.loopxxi.com/mcp

Settings → Connectors → Add custom connector, then paste this address

https://mcp.loopxxi.com/mcp

~/.codex/config.toml

[mcp_servers.loop-mcp]
url = "https://mcp.loopxxi.com/mcp"

.cursor/mcp.json

{
  "mcpServers": {
    "loop-mcp": {
      "url": "https://mcp.loopxxi.com/mcp"
    }
  }
}

.vscode/mcp.json

{
  "servers": {
    "loop-mcp": {
      "type": "http",
      "url": "https://mcp.loopxxi.com/mcp"
    }
  }
}

Available tools 16

Read directly from the server with tools/list, grouped by what they act on. If a tool disappears, we record the date.

btc

btc_price

Get the current Bitcoin price in USD and other major currencies. Source: mempool.space. Real-time. Each reading carries source (the URL read), fetched_at (UTC, RFC 3339) and source_sha256 (SHA-256 of the upstream body as served).

btc_send_decision

Returns a composited send-or-wait recommendation for a Bitcoin transaction. Fetches live mempool and fee data, then outputs a machine-actionable verdict (SEND_NOW, WAIT, or URGENT_ONLY) with fee rates in sat/vB, mempool pressure level, and estimated savings if you wait. Ideal for agents that need a single decision call instead of parsing multiple raw mempool endpoints.

json

json_extract

Extract one value from JSON using a simple dot path with array indexes, for example users[0].email.

json_validate

Validate JSON, identify its root type, and return normalized JSON plus a SHA-256 content hash.

base64

base64_convert

Encode UTF-8 text to Base64 or decode Base64 safely, with standard and URL-safe alphabets.

business

business_ratios

Compute cash runway in months, cash buffer days, current ratio, quick ratio, debt to equity, DSO, DIO, DPO and cash conversion cycle from any subset of a business's own cash, monthly flow and balance sheet figures. Arithmetic only, no network. Each value carries its formula and the inputs it used; a value that cannot be computed is null with a reason.

csv

csv_to_json

Convert CSV, TSV, semicolon, or pipe-delimited text into structured JSON with bounded row output.

decode

tx_decode_explain

Fetch a Bitcoin transaction by txid and return a structured, agent-ready summary: type (P2WPKH/P2TR/P2SH/etc.), input/output counts, fees, fee rate in sat/vB, confirmation status, RBF flag, SegWit/Taproot flags, and a one-line agent_summary string ready for LLM context injection. Saves 500-2000 tokens vs parsing raw TX JSON.

hash

hash_generate

Generate a SHA-256 or SHA-512 digest in hexadecimal or Base64 form.

jwt

jwt_decode

Decode JWT header and payload claims locally without verifying the signature. The response always marks verification as false.

lightning

lightning_address_resolve

Resolve a Lightning Address ([email protected]) to a payable BOLT11 invoice for a given amount. Handles the full LNURL-pay protocol internally. Returns the invoice plus min/max sendable amounts for validation.

optimal

optimal_send_window

Bitcoin transaction timing intelligence. Returns a congestion forecast for the next 1-4h, a recommended UTC send window when fees are projected at/below your target, a fee trajectory (rising/stable/falling) with a calibrated confidence score, next-block minimum fee, confirmation targets for 3/6/144 blocks, and an RBF-viability flag. A synthesis layer above raw fee data — the decision an autonomous payment agent needs before broadcasting. Source: mempool.space.

text

text_analyze

Return deterministic text statistics, estimated tokens, reading time, and a SHA-256 content hash.

timestamp

timestamp_convert

Convert Unix seconds, Unix milliseconds, RFC3339, or ISO dates into normalized UTC timestamp forms.

url

url_parse

Parse an HTTP or HTTPS URL into normalized scheme, host, port, path, query, and fragment fields without fetching it.

uuid

uuid_generate

Generate one to one hundred cryptographically random RFC 4122 UUID version 4 identifiers.

Endpoints

URL	Transport	State	Latency	Checked
https://mcp.loopxxi.com/mcp	streamable-http	answering	408 ms	9 min ago

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loop-mcp — questions

Answers built from our own checks of this server.

What can loop-mcp do?

It exposes 16 tools, read directly from the server on our last check. Among them: base64_convert, btc_price, btc_send_decision, business_ratios, csv_to_json, hash_generate and 10 more. The full list with descriptions is on this page — we take it from the server itself via tools/list, not from a README. How MCP servers expose tools in the first place →

What is loop-mcp mostly used for?

Its tools cluster around btc and json. That is what this server is built to work with — the grouping comes from the actual tool names, not from a category we assigned.

Is loop-mcp working right now?

We send a real MCP handshake every 15 minutes. Over the last 24 hours 91 of 91 checks got a reply (100.0%), average response time 406 ms. The bar chart above shows every period we have measured.

Is loop-mcp still maintained?

The linked repository no longer exists on GitHub — it was deleted or made private. We show this because it changes what you can expect: an unmaintained server may keep answering for months and then stop without warning.

How do I connect loop-mcp?

Copy the ready config from this page. We generate it for Claude Code, Claude Desktop, Codex, Cursor and VS Code, each in the form that client actually reads. It is a remote server, so there is nothing to install — the client connects to the address.

Does loop-mcp need an API key?

No. loop-mcp completed a full MCP handshake with us as an anonymous client and listed its tools without asking for anything. All 16 of them are readable on this page. This is what we observed, not what the docs claim.

How fast is loop-mcp?

It answers our handshake in 406 ms on average, which is faster than 32% of all working MCP servers we measure. The comparison comes from our own checks across the whole registry, every 15 minutes.